Mr Carlson's Ripple Reactor Circuit!
Added 2025-03-04 01:23:14 +0000 UTCHere is the schematic (in the video) and parts to get you building. This circuit can replace an inductor or reactor in many different applications, and perform much better too! The magic is in the component selection (shown in the video). Enjoy!
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Comments
This circuit seems like it was designed really only for use with tube-type equipment, right? I mean, the voltages that you're talking about are far higher than what I ever work with in solid state designs. And there must be a voltage drop across each one of those MOSFETs. And the particular part that you chose for the semiconductors having a 900V source-to-drain breakdown voltage also hints at this.
Dan Butler
2025-12-08 04:23:11 +0000 UTCBrilliant idea. Well done!
Marvin Huff
2025-11-16 21:56:22 +0000 UTCDue to some life issues demanding my time/attention, I won't get to try this for quite a while. Commenting because 8rs (?) ago, starting out, I bought an Elenco XP-625 AC DC power supply to use to learn electronics. This little PSU is un-filtered and un-regulated. I think it has destroyed just about everything I ever connected to it. :D ... To this day, I don't know if it's just that bad, or if I received a defective unit, but when life allows, I plan to tear it apart, verify that it's not defective, and then maybe construct a filter and regulator to make it "whole and useable". If I want to destroy something, it's perfect right now. :D This ripple tamer circuit is very interesting and might become part of the solution for the "Killer, The PSU" to become stable and more like "Hans Delbrück" than "Abby Normal". Maybe a project of value for a video, Paul.
Stephen Martin
2025-08-03 01:51:11 +0000 UTCPeople do exactly what you describe all the time. If you are concerned about noise just mill the rest of the copper away. Or if its a large connected pad attach it to ground. It really depends on the circuit. Most of the time it won't matter.
jeffrey wagner
2025-05-01 13:32:04 +0000 UTCGood evening. I just joined today, and I just wanted to say I enjoy all of the videos I've seen so far. I was wondering with this circuit, could I use my cnc on a copper board to etch the traces. only the non-copper part, so I would be leaving the remaining copper. Would I run into issues with interference? Should I ground the rest of the board...
Matthew Doty
2025-04-09 02:16:19 +0000 UTCThis is really a nice deal here. Thanks for all of your hard work.
Leonard Peters
2025-04-04 20:27:06 +0000 UTCI'd love to see a comparison between the solid state and the tube version sometime.
Brendan White
2025-03-20 00:45:31 +0000 UTCI'm told that the ND means "No Discount". I expected it was sarcasm from him, but the fella was serious.
Scott Morgan
2025-03-18 03:06:31 +0000 UTCThank you!
Dave Achterberg
2025-03-12 16:54:22 +0000 UTCHas anyone tried modelling this in LTSpice? I have just tried and am not getting expected results, and that is using the ST Micro .subckt for the device, not any old NMOS.
Richard Kelly
2025-03-12 08:07:27 +0000 UTCIt's on You Tube. Select the Green AM Motorola radio repair video, very recent. The hum investigation is past the middle of the 3 hour video.
Mike
2025-03-10 14:20:05 +0000 UTCMike where can I find Mr Carlson’s method hum investigation? Is it in a specific video?
Dave Achterberg
2025-03-10 11:57:28 +0000 UTCI was wondering what are the operating limits of this device? High and low voltages as well as maximum current. I can imagine we will see this in future videos. How excited were you when you saw how well it worked and how simple it was?
Richard Goebel
2025-03-09 19:15:28 +0000 UTCI watched this earlier and another video where you repaired a choke. I checked a choke that was installed right off the main transformer with my Tenma tester. I was checking a 9H 335 ohms. My readings was 9.720H and 322.5 ohms. I think the choke is fine.
Billy Sharp
2025-03-09 17:36:39 +0000 UTCHow come the first stage is drawn different then the following stages? Is this some convention? Also, I was wondering what "-nd" means in the part numbers, Found this: “ND” once stood for “No Discount” back when the paper catalog displayed a listing of discount percentages based on quantity. Today, “-ND” has become a DigiKey signature allowing people to know that a listed part number is available at DigiKey. Many times the part numbers are the manufacturer’s part number with a simple -ND added to the end.
David McAnulty
2025-03-08 19:21:27 +0000 UTCYes, thank you. Very simple circuit and effective! Looking forward to seeing the circuit board and if you decide to change anything.
Chris Bennett
2025-03-08 01:19:49 +0000 UTCPaul, I want to thank you for this article AND the YouTube regarding the Green radio. I've just completed restoration of a Zenith 12H670 radio. I also added a Bluetooth to it and it works fine. BUT, I had some HUM that I thought was not correct. The B+ is very good with only about 5 Mv of ripple. Then I tried your method of HUM investigation and found that although I had shielded cable between the VR and the first stage of Audio, I had a coupling cap right at the VR. Seems this little open area was picking up AC hum from the ON/OFF switch. My solution was to move the cap from the VR and place it short leaded to the 1st audio stage and run the shielded cable from the cap directly to the VR. The results were great! Again Thanks a million.
Mike
2025-03-06 16:45:58 +0000 UTCGreat circuit can not wait till schematic and parts list come out. Will be building this for my radio restorations. Thanks!!!!
Gloria Jill Sydor
2025-03-06 15:37:48 +0000 UTCTiming on this is perfect! Going to try this out on a tube headphone amp project. Ordered the parts while the video was running. Please get into the details of how this works in the next video. Thanks Mr. C.
Stanley Benoit
2025-03-05 12:38:43 +0000 UTCThanks for the insight. It was indeed something people on DIY Audio were doing to filter walwart smps for DAC's etc.
Warren Jackson
2025-03-05 09:19:08 +0000 UTCAs far as I can tell (as someone who is still rather inexperienced at actually making electronics) it's basically the same as what some people call a capacitance multiplier. I think there is some question about how good a name that is for this particular type of device. Maybe a "transistor amplified RC filter" would be a better name, but, I that's my two cents. In effect, it could be considered to amplify the -effect- of the capacitors in the circuit, but, it could equally be considered to multiply the effect of the resistance, AFAIUI. I think maybe amplifier people have called it a capacitance multiplier because the filter caps are emphasized as being there but they don't necessarily have actively added resistance or inductance to the circuit, so it's thought of most in terms of the capacitance.
Michael Shor
2025-03-05 03:26:48 +0000 UTCHay Paul. I noticed on your restorations/repairs that you use a protective covering on the legs of the replacement part, especially if the wires are long. Can you tell me what that is called. I would like to purchase some. Thanks. Rick
rts12309
2025-03-04 23:43:29 +0000 UTCWould love to see a list of clever alternative uses for this!
Dan Gonzales
2025-03-04 23:07:54 +0000 UTCNice video as always Paul. Interesting use of Mosfets. How does the ripple reduction of this circuit compare to a linear voltage regulator?
Svein Arne Netteland
2025-03-04 21:01:18 +0000 UTCStill have to watch the rest of your 3hr video to see this in use in the all american radio, but this looks to be a useful ciruit to file in the "that'll do the job folder". Thanks. btw when I can't find tools or components I have been using I search the big shelf first, they are often down there.
David Moule
2025-03-04 20:02:25 +0000 UTCLook forward to seeing all the final plans!
Ted Mieske
2025-03-04 18:41:11 +0000 UTCExcellent project Paul, as always! Thank you! Quick question, is this RR circuit will remove slight hum that I always get on late 50's tube amps? This amps almost never have choke in PS circuit
Aram Baloyan
2025-03-04 18:18:12 +0000 UTCI like learning something new everyday (and soon forgetting that new thing - lol). Ihave worked in electronics ~45 years. I have never seen an active ripple reducer like this; thank you. We were not taught anything like this back in Electronic School in 1979-1981. None of the equipment I have worked on in these last 44 years have anything like this and some of them could have used better filtering. Can a circuit like this work at lower voltages or does it become difficult is needing to draw an amp through it?
David Kuhn
2025-03-04 18:16:24 +0000 UTCVery nice , will try it out.
richard ockman
2025-03-04 17:50:42 +0000 UTCYes, 23V Peak to Peak, with the 47uF cap. After the ripple filter, about 20mV ripple.
Mr Carlson's Lab
2025-03-04 17:33:04 +0000 UTCThanks. Interesting. I was watching the video, expecting an explanation later in the video, so didn’t pay too much attention to the schematic. I would have eventually figured it out, but your explanation saved me some time thinking about how it works.
Casey
2025-03-04 15:29:26 +0000 UTCI admit very little experience with the AA5 radio involved in this series, but am a bit confused as to how/why the radio's 1/2 wave rectified power supply creates such a perfect saw-tooth ripple.
Donald Stevenson
2025-03-04 13:57:12 +0000 UTCNice! Is that similar to a capacitance multiplier?
Warren Jackson
2025-03-04 11:36:42 +0000 UTCAlways learning something new (old) stuff 🙂
Mika Juurikivi
2025-03-04 10:42:11 +0000 UTCWhat a great little module. That will come in useful for so many things. Thanks for producing this
Alan Drury
2025-03-04 10:14:14 +0000 UTCSo the 145V DC supply has 23V ripple?
John Puma
2025-03-04 07:32:00 +0000 UTCI love this circuit and my personal thoughts are getting rid of a big high voltage electrolytic capacitor with an expected MTBF characteristic is a win. getting rid of a big, expensive, iron core reactor is another win. So I see this circuit as very desirable where you want your D.C. power supply to run reliably for many years.
Kenneth deGruchy Jr
2025-03-04 07:06:05 +0000 UTCWith the flawless candy green paint job!
C Knob
2025-03-04 05:15:40 +0000 UTCGreat video. So glad to have a reactor replacement circuit.
Sheldon Butler
2025-03-04 04:46:23 +0000 UTCThe resister (first one) and capacitor together form a low-pass filter, which controls current flow through the FET. So only slowly-varying AC makes it through. Repeat 3 times.
Jerry Malone
2025-03-04 04:04:51 +0000 UTCNice! I'd never heard of this solution for ripple control. Does this mean that all those radios with blown reactors can be brought back to life without having to rewind the coil or search for a replacement from a donor radio? That's a great solution, and I like the idea of hiding the circuit inside the bell housings of original reactors. Goes hand-in-hand with the restuffing of dried out filter capacitors which I'm sure we've all done at one time or another. Thanks, Paul!
kmpres
2025-03-04 03:47:16 +0000 UTCNeat circuit. I too, would like you to explain the theory behind how this circuit reduces ripple.
Casey
2025-03-04 02:43:35 +0000 UTCThe all American 5 green
rts12309
2025-03-04 02:08:20 +0000 UTCIt's in my latest YouTube video, launched yesterday.
Mr Carlson's Lab
2025-03-04 02:07:07 +0000 UTCGreat video!
Billy Sharp
2025-03-04 02:05:51 +0000 UTCHi Paul this is a really great circuit and I wasn't aware of this method of reducing ripple. For some reason I don't grasp the theory behind it. Maybe you can also explain how the circuit does its job. Thanks for the video and looking forward to the next one.
Scott Gilbert
2025-03-04 01:57:33 +0000 UTCI literally just got to the section of your YouTube video where you talk about this circuit. What a legend, Mr. C! Thank you
Chris
2025-03-04 01:52:19 +0000 UTCHay can we see it installed???
rts12309
2025-03-04 01:50:55 +0000 UTCExcellent thank you!
Robert Thresher
2025-03-04 01:46:00 +0000 UTC
